Our goal is to correlate the antibody response to melanoma vaccine immunization with clinical outcome in patients with stage II melanoma. The specific aims are to: 1) Measure the antibody response to melanoma induced by immunization to a prototype, polyvalent, melanoma antigen vaccine. The level of antibodies to individual melanoma cell surface antigens will be measured prior to and at specified intervals following vaccine immunization in patients with stage II melanoma who have been entered into clinical trails with melanoma vaccine. 2) Correlate the antibody response with clinical outcome, as measured by disease-free interval. This proposal exploits two new developments. 1) A recently developed assay which permits the measurement of antibody responses to individual antigens on the surface of melanoma cells. 2) A bank of serial sera specimens collected from 140 patients with stage II melanoma prior to and at intervals following clinical trials with a melanoma vaccine, together with matching clinical follow-up information. Successful completion of this work will provide information critical to the development of melanoma vaccines - the identity of melanoma antigens which can stimulate immune responses in humans and the relevance of the antibody responses they induce to tumor progression.